A successor, in name only, to https://gist.github.com/Grissess/6af0bcb8fe46e81b9a5f39bed03b9271 .

blockletter.py

import argparse

MAP = {
        'A': ['  *  ', ' * * ', '*****', '*   *', '*   *'],
        'B': ['*** ', '*  *', '*** ', '*  *', '*** '],
        'C': ['****', '*   ', '*   ', '*   ', '****'],
        'D': ['**  ', '* * ', '*  *', '* * ', '**  '],
        'E': ['****', '*   ', '****', '*   ', '****'],
        'F': ['****', '*   ', '*** ', '*   ', '*   '],
        'G': ['*****', '*    ', '* ***', '*   *', '*****'],
        'H': ['*  *', '*  *', '****', '*  *', '*  *'],
        'I': ['***', ' * ', ' * ', ' * ', '***'],
        'J': ['****', '  * ', '  * ', '* * ', ' *  '],
        'K': ['*  *', '* * ', '**  ', '* * ', '*  *'],
        'L': ['*   ', '*   ', '*   ', '*   ', '****'],
        'M': [' * * ', '* * *', '* * *', '*   *', '*   *'],
        'N': ['*   *', '**  *', '* * *', '*  **', '*   *'],
        'O': ['****', '*  *', '*  *', '*  *', '****'],
        'P': ['*** ', '*  *', '*** ', '*   ', '*   '],
        'Q': [' ** ', '*  *', '*  *', '* **', ' ***'],
        'R': ['*** ', '*  *', '*** ', '* * ', '*  *'],
        'S': [' *** ', '*    ', ' *** ', '    *', ' *** '],
        'T': ['***', ' * ', ' * ', ' * ', ' * '],
        'U': ['*  *', '*  *', '*  *', '*  *', ' ** '],
        'V': ['*   *', '*   *', ' * * ', ' * * ', '  *  '],
        'W': ['*   *', '*   *', '* * *', '* * *', ' * * '],
        'X': ['*   *', ' * * ', '  *  ', ' * * ', '*   *'],
        'Y': ['* *', '* *', ' * ', ' * ', ' * '],
        'Z': ['****', '   *', '  * ', ' *  ', '****'],
        '0': [' ** ', '*  *', '*  *', '*  *', ' ** '],
        '1': [' ** ', '  * ', '  * ', '  * ', '****'],
        '2': [' ** ', '*  *', '  * ', ' *  ', '****'],
        '3': ['*** ', '   *', ' ** ', '   *', '*** '],
        '4': ['  * ', ' ** ', '* * ', '****', '  * '],
        '5': ['****', '*   ', '*** ', '   *', '*** '],
        '6': ['  **', ' *  ', '*** ', '*  *', ' ** '],
        '7': ['****', '   *', '  * ', ' *  ', '*   '],
        '8': [' ** ', '*  *', ' ** ', '*  *', ' ** '],
        '9': [' ** ', '*  *', ' ***', '  * ', ' *  '],
        ':': [' ', '*', ' ', '*', ' '],
        ';': [' ', '*', ' ', '*', '*'],
        '.': [' ', ' ', ' ', ' ', '*'],
        ',': [' ', ' ', ' ', '*', '*'],
        "'": ['*', '*', ' ', ' ', ' '],
        '"': ['* *', '* *', '   ', '   ', '   '],
        ' ': ['  ', '  ', '  ', '  ', '  '],
        '-': ['  ', '  ', '**', '  ', '  '],
}
DEFAULT = ['*  *', '*  *', '    ', '*  *', '*  *']

parser = argparse.ArgumentParser(description="Make block letters.")
parser.add_argument('text', help='Text to display')
parser.add_argument('--spacing', type=int, default=1, help='Space between letters')
parser.add_argument('--mark', '-m', default='*', help='Character to display when pixel is set')
parser.add_argument('--space', '-s', default=' ', help='Character to display when pixel is clear')
parser.add_argument('--hide-missing', action='store_true', help='Don\'t show missing characters')
parser.add_argument('--scale', type=int, default=1, help='Scale of the blocks')

def justify(blocks):
    width = max([len(row) for row in blocks])
    for idx, row in enumerate(blocks):
        if len(row) < width:
            blocks[idx] += ' ' * (width - len(row))

def concat(blocks, block):
    while len(block) > len(blocks):
        blocks.append('')
    justify(blocks)
    for idx in range(len(blocks)):
        blocks[idx] += block[idx]

def shift(blocks, amt, char=' '):
    justify(blocks)
    for idx in range(len(blocks)):
        blocks[idx] += char * amt

def block(text, mark='*', space=' ', spacing=1, hide=False):
    blocks = []
    dfl = None if hide else DEFAULT
    for idx, ch in enumerate(text):
        block = MAP.get(ch, dfl)
        if block is not None:
            bk = [''.join(mark if i == '*' else space for i in s) for s in block]
            concat(blocks, bk)
            shift(blocks, spacing, space)
    return blocks

def scale(blocks, fac):
    return [''.join(c * fac for c in s) for s in blocks for rep in range(fac)]

def main():
    args = parser.parse_args()
    blocks = block(args.text, args.mark, args.space, args.spacing, args.hide_missing)
    if args.scale != 1:
        blocks = scale(blocks, args.scale)
    for line in blocks:
        print(line)

if __name__ == '__main__':
    main()