Another source for transformers is control power transformers from switchgear. They come with 2400, 4160 or 6.9kv primaries and up to 5kVA. They are built to last. We have some 4160 switchgear that is 50 years old and the CPTs are just fine. I got a 2300-208 with taps on the 208 winding 5kVA for about $800 including shipping. Brad AB0YD