I was in a similar boat with my Trep at 205K... after looking at the local market and the shape of the rest of my vehicle, I put another engine in it. Did not replace the transmission. The replacement engine had 73K on it; I did not have faith in my ability to install so I had a shop do it for $3100. If I had found a low mileage Trep for less I'd have possibly gotten one, but I realized that any trep I got would probably be over 100K, and if I didn't have evidence of a timing belt/water pump swap, I'd have to do that right away.
Basically, I ended up asking myself "If I found a Trep in this condition, with 205K miles but a 73K engine on sale for $3200, would I buy it compared to the other vehicles I am seeing available?" The answer was yes, so I went ahead with the swap, and I've been happy with it. Of course that commits me to this car for several more years, and yes the tranny is my biggest worry, but overall (six months later) I'm happy with the results.