i get all my stuff from here, http://www.cfsnet.co.uk

it can be quite pricy as an example, all the stuff i needed to do this bumper mould and probably enough left to make about 3-4 bumpers cost me around £350

you have to remember that you need resin, gel coat, tissue, glass mat, cleaning acatone, brushes,rollers,superglue, superglue activator, release wax, pva sealer, vent mask, buckets ect. it all adds up
then you would really need an air saw for trimming suff out as its pretty shit trying to do it any other way.

for a set of side skirt moulds and a set of new componets your probably looking at about £200ish to be on the safe side.