I see triumph bags on e bay all the time ,I think the bags and the seat cover are all the same,we have 2 sets tt600 and sprint rs,
they are identical ,only the panel protectors are bike specific,so you could save alot of money by getting a use set. There is alot of hard ware for the panel protectors, i think those would be best bought new. As some people forget to take it off when they sell or wreck a bike.
The triumph bags are excellent luggage !