You should be able to buy the Casseroll as a Frame only – I bought mine from Wiggle. Looks like they only have a 53cm available so stock may be getting scarce. They size up about 3cm smaller than a standard frame so a 53 has a 56cm equivalent top tube. They also have quite a high front end. If it any help, I'm 5ft 10 and the 53 fits me perfectly – most comfortable bike I've ever ridden!