If you just need cheap and decent, and you are willing to go with transformers that are similar to Fenders and Marshalls, about the cheapest good quality around is Ted Weber's offerings.
www.tedweber.com . They are made in Asia but are quite good.
Heyboer are more expensive, but very good, and they will build you something to suit. Mercury Magnetics makes some great stuff, but is way overpriced to my eyes. Once you buy enough of them, then you get into their preferred camp, and then their transformers are just a bit overpriced, but you will have spent a lot of extra money to get to that point.
Greg