Anyone know how to order them for less than full retail? Thanks!

Hey guys so I have a question, I have a sti tactical 4.0 black out edition 2011 that I’m going to add into my carry rotation but my question is….is it possible to maybe switch the grip out for maybe a smaller grip like the staccato c2 size (120mm) ? If can someone share any pros and cons also...

Having a hard time finding an iwb holster for the sti tactical 4.0……all I find is for the staccato P 4.0 my question is will the sti tactical 4.0 for the staccato P 4.0 holster ?