The problem is a well known one in the calculator world. Articles like this one should give you a few ideas:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=57

The mechanism itself is a QIC tape, so look around for info about them. Information about tape speed (ie physical metres per second) should give an indication of the required mechanical properties of a replacement roller, home made or a subsitute from another device. A tape drive roller rotates more quickly than a roller in a printer or calculator, so good luck.