If the reflector is similar to the SP32/SP32A, a regular TIR fits in diameter, but probably not in height.
I moded my SP32A with a TIR I had from a cheap SS light! You can take a look at it here: UPDATE! "REVIEW" & Mods: Sofirn SP32A [It is now a TRIPLE :D ] (Pic Heavy) - #14 by MascaratumB
Please note that this TIR is taller and larger in the head that the regular TIRs (at least without the “shoe”).