I had these done by Triple R knives. But, other knife builders who can drive out bolster pins and re-pin new blades without damaging bolsters or leaving gaps could do about the same. BUT, pay attention here, you should use only the sawcut black scale version, because then all they have to do is to knock out the bolster pins, grind off a spring pin head and drive the pin out the other side, remove the spey and spring and replace the three pins and your done. You still have your black sawcut scales in place. With the Dymondwoods and smooth yellow scale versions you have to remove the scales to do the modifications because the spring pin is HIDDEN. If you still want to go to two blades with those versions I would plan to put on some new fancy bone, stag, burl wood, jigged bone or horn scales while they are off. Paying someone to put the old scales back on and redo four pins seems counterpoint to me.
Yes, the spey is a fancy and precise slicer and if you like to have one then you are already set. I can get by with the clip doing that work and would find a strong full length warcliff blade a helpful addition, while making for a slightly slimmer in width knife.
The ideal 319 Rancher version for me would be one with the smooth stainless awl, a sheepsfoot or warcliff blade along with the traditional clip blade. That would be a darn good knife. Toward the rear of the awl, I might add a couple of small notches that would not mess with the awl working for stripping copper wire. 300