I'd go find a mechanic who knows something about skis, and see what you might be able to put together. Give Burl Rogers a call at Lake Hood, and see what he has to say.
As Don says, you're not going to have a "Go anywhere" ski plane in any case, but if you just want to go from groomed strip to groomed strip...... And, frankly, a stock 170 on skis falls into pretty much the same category.
But I suspect you're going to have to get something field approved, and as one poster noted, it may be cheaper/easier to switch airplanes if you really want a ski plane.
That said, go back and read Don C's notes in this thread.....that pretty much applies to ANY ski plane operation at some level.
MTV