Afraid you may need a custom machine shop to make it..

#1.. suntour 2 prong freewheel puts it back to being 30 years old.

(I toured Europe, with a 50:14, a lot. the High 95" gear was fine.. 3.5:1)

put a huge chainring on the crank , or better, buy a new bike.

modern cassetes on road-racer wannabe start at 11t, with a 53t chainring
4.818: 1..

120 dropout frames, the 5 speed era , are good for fixie conversions,
so you can find a buyer for your old frame and old parts.
[value is what they are willing to pay ]