There are a couple ways you could go about it.

Get a new set of standard dropouts if yours is not. Frame builder can braze the new dropouts on but it will ruin the paint. If you can live with a big splotch of burnt metal on the seat and chainstays you are done. If not you can get the frame painted ($$$$) or powder coated ($$$). Add decals into the mix ($$).

Or get a new frame and move the parts over.