I don't suppose anyone here would know where I could source one of these Marbles peep sights or another brand that would work on the modern 86 with the lawyer's safety?

http://homesteadparts.com/shopcart/pid_1960.htm

I could probably persuade one of the US firms to send me one or even get it from the UK, but with all the panic over parts imports these days, that could end in tears.