Unless you're set up with the machinery to dovetail a slide, I would think that a DIY solution would be more likely if you found an adjustable rear to fit the factory dovetail. I don't know for sure if the RIA shares the dovetail dimmensions of the original govt. model. There seem to be a few adjustable rears for the govt. dovetail, though they may also require staking a taller front sight.
As a fellow RIA owner, I'm curious about this as well. Anyone certain how the RIA dovetail stacks up to the original?
Edit: Most of what I've read says it is a G.I.-spec dovetail, but I haven't a G.I. gun to which to compare it to be sure.
I had Meprolight night sights for the "Govt Model" installed on my RIA and the rear dovetail fit perfectly. However, the RIA uses a thinner front tenon so the Meprolight front had to be thinned to fit. HTH...
Put Kings hardball sights on mine, standard Colt government rear dovetail and standard narrow tenon .125 front sight,they have other styles also.You can also check www.precisionsights.com for adj. sights.