my upgraded powerflex ones cost just over £40 for the part. There is no point in not getting them because they are actually easier to fit than putting standard ones back in.
The old ones are a proper pain to get out. We were absoloutely belting the crap out of the drivers side with a hammer and chisel.
We tried air sawing into it and it still wouldnt budge.
In the end we had to warm it up slightly to get the thing out.
Some places wont even change them for you because they know how much of a pain they are.
If the guy would supply and fit powerflex ones for £150, its prob not too much of a bad shout,
see if anyone else on here can referr you to someone cheaper