Dear @skyscraper : " whereas I’m only in the minor leagues..."
Well, problem is your knowledge level on the whole issue.
Look, today almost no one is looking to buy ( second/third hand. ) the VPI rig model you own that's out of production and as you leave that time goes on/pass your unit re-sale prices will and is lower and lower faster than you can imagine. In the other side your VPI tonearm is not a " desirable " one for any audiophile.
You are talking that over time buy the 4.5K VPI FB tonearm and this is up to you.
Now, you get for 4K a new and way better TT/tonearm combination that works just fine with the Kleos and almost any other cartridge and that TT/tonearm is the Technics 1200G, way superior to what you own today and this could be your alternative not the FB. Again, is up to you.
R.