`The OPT's (output transformers) are really what defines the sonics of a tube amp and I think you want SE . You might end up with poor ones for all that money and the rest of the parts you will end up upgrading. $300 could buy some really nice OPT's and affordable PS made in the US with nice quality tubes and caps etc. Maybe save up for some really good OPT's as very important in SE and you could later use them in a nice DHT amp later when you have a bigger budget.
KT-88 tubes would be a step up in most peoples opinion for SE. More bandwidth and less distortion. But ones mentioned below support them if re-biased for them.
Kegger SEUL SE amp on this form.
http://www.audiokarma.org/forums/showpost.php?p=5651746&postcount=184
Look at tubelab George's SE and DHT SE PCB's on his website and more info (lots) on diyaudio. Lot's of support and well liked. Use Edcor OPT's for low cost start. Use at least GX 15W OPT's.
If you want P2P Micheal Abdelah's popular SE KT-88 schem. is out on the forms. There was a full kit and partial from a member on diyaudio.
If 3W/Ch is enough with 6550/KT-88 tubes check out Transcendent Sound Cathode Follower Amp plans on his site. Bottlehead 2A3 kit has been mentioned as very well liked on this Form in the last few days to a week by a member if in your power range needed and budget.
There are PCB's on the diytube site of simple SE designs also.
