Hi, Ive a Viking hiding in the shed but I will need to stick a tape over it to get the size, needs renovation but I can get measurements and pics over the weekend if you are interested.
Just had a quick look. its a Conquest model probably 60s as it had a 5 speed Cyclo derallieur on it when I got it (I still have it somewhere)
measures 22" on the seat tube and 23" on the top.