I bought a 1997 a few months back with 43K miles and a tiptronic. I too had read the horror stories on the forums. I figured for peace of mind even though the car was low mileage the car was 17 years old I would have my local Indy mechanic drop the engine and go through everything and do the IMS at the same time. I had him install the EPS IMS fix. You can watch a video about it here:
EPS IMS Oil Lubrication on Vimeo
I also had him change the plugs and tubes, belt, water pump, every rubber coolant hose, fuel and air filters, Air/oil separator tank, the Idle control valve (was throwing a CE code), and front engine mount. The parts and labor together came to about $2100. My IMS bearing was still good but the water pump was starting to wobble so it was good that I changed it. I paid $11k for the car and it had new tires and a new top on it. Knowing that Pretty much every possible issue has been addressed has given me the peace of mind to know I have a dependable driver and I am not worried about pushing the car to the limits it was designed for and am expecting many, many more miles out of the car. If you are worried about it find a good reasonable Porsche mechanic and get the work done. The car will still be worth what you put into it and you cad drive it and enjoy it with peace of mind. This is my 23rd Porsche and my favorite one so far. BTW, since you have a manual trans I would check out the clutch, pressure plate and Throw out bearing while you are in there. Have fun. Join your local PCA Regional club. You will meet some great people and they are loaded with experience and knowledge.