Hi Andy - I sold my 1999 ten-top McCarty some years back - maybe 2015 - for around $1800. Add inflation since then and you're in the right ballpark at $2-2.5K.
My free advice: Buy a newer one. It's nothing dramatic, but they keep getting a little better over time as PRS just keeps on sweating the details.
The biggest improvement is the 57/08 pickups. I sold my '99 because the stock McCarty pickups were just dull. I tried SD Alnico IIs and that helped. But nothing sounded as good as the 2009 McCarty I bought used in 2015 that had the 57/08 pickups stock. End of that search - it's a keeper.
PRS has finally fixed the one real beef people (including me) have had: The pickups. The 50-series (57/08, 58/15, and the late and much lamented 53/10s) are wonderful vintage style pickups that I bet you'd like.
I'd also like to throw in a plug for the McCarty 594 version. Again, incrementally better over time - and the 58/15s are great pickups. Those will cost more, but see if you can get one for $3K with some patience.
Good to see you here, and I hope you've been well. Shoot me a PM and let's catch up.
-GeoKiwi