I have been in the market for a tube box for the house that can give me a easy 1kw to run with my rci 2990, I am eyeing one of these up so any input would be great!

Not a bad amp for SSB use. Dentron amps left a lot to be desired in the PS department, IMHO (much like Heathkit) so I wouln't press it too hard on AM. And 572B's should be available for quite some time, in one form or another.

__________________
"Fat girls need lovin' too...they just gotta pay." --Glenn Quagmire

This amp is most likely at least 25 years old...most were built mid to late 70's...when mil-spec 572B's were $15 to $20 each...with only Russian and Chinese available now on regular basis they will run about $150 a set in matched groups....which is the best way to go...
The Russian Svetlana are the better I think but require some mods to the amp as they are not exact replacements for the old mil-spec US versions...The Better of the Chinese are the PENTA brand but are getting harder to find (about $30-$40 each in matched sets of 4).
This will give a KW PEP output on SSB only...maybe a bit more if power supply in good shape...
AM Service:With about 25 to 40 watts drive...
AM MAX modulated output should be no more than 500 watts...anymore than that and the power supply is screaming for HELP...
it's your dime...Good Luck
All the Best
BJ