Hey Turbo Guys

So I have a 78 Dodge C-Class motor home with a 440 that I would like to modify for better performance at some point. At first I thought stroker but now I am entertaining turbo with low boost .
And since there is so much room under the chassis behind the engine I figure going with 2 small turbos mounted directly to header collectors would be the ticket .

Question is ....which turbos to use ? How big ? Are there low buck ones ? How cheap could I do this and still be reliable ? What are the challenges to this.?

I have zero experience with turbos.

Thanks