Yes, sights that are described as being for a Mark II are compatible with a 22/45, as the barrel/receiver assemblies are the same on the two different models - I'm assuming that your sights are adjustable. For iron sights, Millet makes a nice set. I think that Brownell's sells them for around $60. I can't remember where, but I know that I have seen either the Millet or something close to it for around $30. I'm still looking.