Most garages will replace the Head bolts on most occasions when refitting the head. Lots of vehicles have STRETCH bolts now, which alloy an alluminium head, and a cast engine block to move indipendently. This is the role of the head gasket. Ally and sttel both expand andd contract at different rates, so the bolts take up the movement, but still keep them pulled together.
When the bolts are removed, they can distort, and when you put them back, not do as they should.
To reduce comeback on the garages part, this is why they usually insist on the bolts being replaced.
They may ask you to sign a disclaimer if you do not. But as the manual says they can be reused, i doubt it.
Try
www.paddockspares.com they should have them cheaper than that.
A set of 18 cylinder head bolts are £32+vat for the 200Tdi. They dont have the Mpi bits online, but should be able to supply them.