you can get the single sided safeties in the Standard, Extended, and Gold Team lengths. As was already stated, they are interchangable on all of the elite series large frame guns (Stock II, Stock II, Lim Pro, Limited, Gold Team ect). They are factory parts and are production legal.
I have the ambi Gold Team safities in Silver in stock if you want one. I have all of the rest avaiable in Black, single or ambi.