All Triumph spin-on filters are the same. They don't vary bike-to-bike. The automobile filters listed below tend to be longer, but shouldn't be a problem on your bike (makes a difference on a Bonneville where they stick down).
Motorcycle-Specific filters:
AC Delco PF2135
AMSoil SMF103
Fram PH6017A
Honda 15410-MCJ-000
K&N KN-191 (Has a metric nut on the end for easy removal)
NAPA Gold 1358
Carquest 85358
WIX 51358
Purolator Motorcycle ML16817 (imported filter)
STP SMO 07
Automobile Filters (about 2.5" long):
Mobil M1-108
Purolator Pure One PL14612
Bosh 3300
WalMart Supertech ST6607 (made by Champion)
AC Delco PF1237
NAPA Gold 1365
Purolator L14622
STP S-02876
Baldwin B1400
Hastings LF113
Frams are crap by the way. They came out on top in a Consumers Reports test because they were hard to clog. They're hard to clog because they don't filter anything.