Twin exit bumpers

[Davie b]

Hi guys , I'm booked in for a stainless exhaust system next week and like the idea of a twin exit system but don't like the idea of cutting a hole in the bumper / diffuser part to accommodate it .
So my question is was there/ is there a bumper that came with built in twin exit slots that I can fit , are there any after market ones and if so where do I get them and also does the whole rear bumper need replacing or can you just get the plastic lower skirt/ diffuser part and change that with the original one ,
Cheers
Dave