I assume you're talking about the factory overbored barrel that came with Trap Full, Trap Extra Full and Trap Super Full chokes? Any Remchoke will fit the threads, but because the barrel is overbored the constriction will not match what is printed on the choke. For example, an IC Remchoke in the overbored barrel will result in around a nominal .027" constriction, which is normally considered Imp Mod. In a regular barrel, that IC choke gives .009" constriction which is IC. Here's a link to a chart at Remington's website that lists all the nominal constrictions so you can determine what they would be in the overbored barrel. http://www.remington.com/products/accessories/gun_parts/remchoke_specs.asp
I have a 1989 Remington TC that came with those 3 chokes but I've found in this gun the normal chokes such as regular full works fine, I also have a 1990 Remington 11-87 trap that remington said was backbored but again it shoot the normal chokes like its supposed to so I'm wondering if those barrels were even backbored? they don't shoot like it.