Peter:
5 liters of Xtol can be replaced by 200 ml of PC-TEA stock solution. It is diluted 1+50 to give about the equivalent of the Main-iac's version. It is very good stuff by all reports including mine.

In case you missed it somewhere along the line, get some triethanolamine (TEA), some ascorbic acid (erythorbic acid is as good) and some phenidone. Mix 200 ml of TEA with 18 grams of ascorbic acid and 0.5 grams of phenidone and heat the mixture until it dissolves. It may have to go to 180 F or so. This will make 10 liters of 1+50 working solution that should give fairly close to the developing times you are using, but please make a throwaway test first.