saiga 308

I picked up a used saiga 308 a little while ago. The top cover of it has a see through box and picatinny rail for a scope mount. I want to replace it with a standard cover and get a side mount scope rail. I can't seem to find any. Everything I have found have some kind of rail already on it.

Now to my question. Can I just replace it with a standard cover from an ak-47? I have looked at quite a few sites for the part I am looking for (starting with this one) and just can't seem to find what I am looking for so now I am looking for an alternative. If someone knows where I can find what I am looking for or knows if I can just pick up a plain ak cover and replace it I would greatly appreciate any info that I am given.

Thanks in advance for the help.