2004 Chevy Avalanche

2nd Owner, purchased at 56,000. Original owner was on a 2 year lease. Well maintained and loved over the years. Mechanical Transmission - Third gear is gone; it has troubles shifting into third gear. First, second and reverse are fine, and all the others if you can get past third. Shifter Cable - The shifter cable has worn out. I did a temp fix so it can still shift fine. I purchased a new shifter cable and was going to replace it, but then my transmission went. Pressure Release Sensor for the fuel tank - This is no longer functioning properly and probably needs to be replaced. The only thing it affects, besides the engine light staying on, is that it doesn't vent the pressure properly on the fuel tank, causing the nozzle to kick out sometimes due to the pressure build up in the tank when fueling. Everything else is mechanically sound. I had to swap out the engine at 130,000 km (defective heads), so the engine currently has around 171,000 km on it. I've kept up with everything else required along the way (brakes, wheel hubs, U-joint, shocks, etc.) . Other Cosmetic or Functional Items There is some rust, including in the driver floorboard. The driver's seat is completely worn out. I've been looking for a replacement for a while but could only ever find all the other seats. I was looking into rebuilding it; you can find all the replacement parts on ebay or amazon. No body damage, besides the rust, just some light scratches and the clearcoat is wearing away on the tailgate. Everything else is in decent shape, just showing its age. The truck could be fixed up to get more years out of it as many of the parts are still readily available and are interchangeable with a lot of the Tahoe and Silverado parts of the same year range. Or it could be a good parts truck as it still has a lot of good parts to it. I'm asking for $4,000, but I'm open to offers. Let me know if you are interested and if you want to take a look.