Power Transformer

[azrael]

Looking at buying a new transformer so my amp will be able to make the switch from 6L6s to either EL34s or KT88s.
The current power transformer can't supply enough current to the heaters.
4 12AX7s, two octal power tubes.

Now, my options are:
- to either replace the current one completely, so I figure I'll need a minimum of 4 amps for that option. I usually see them around 5A or 7A, though.

- to get a smaller transformer that maybe just has a 6.3V tap, that can do a around 3.5A, and run only the power tubes off that.

So my question is, where can I buy a transformer like this?
Where do you guys buy your transformers?

Looking at something affordable, which is why I'm willing to try the second option I mentioned.

[Firestorm]

Hammond 166N6: 6.3VAC, CT, 4A -- under $16 from Mouser.

[azrael]

You sir, are a gentleman and a scholar.

[Prairie Dawg]

You can power up your existing rig, take measurements of voltage, power it up with the new setup and see how much voltage you lose. You might find more in there than you supposed.