Who do you recommend for Integrated Amp Mods?

It is associated to your budget.
I never heard and even didn’t know your amp.
IMO when you want to get an Upgrade for amps the way is change for a Class A.
Try to know and hear Class A amps.
Dont forget: IMO

Well tonight I put some nos Philips tubes in the preamp board. Wow really nice difference. Much more liquid and smooth with more body to the mids. 

I think tube rolling will be best for you. After a quick google search it looks like a pretty simple preamp, with some really nice caps in it. 
If it has the separate power supply, that could possibly be a candidate for some upgrades depending on the components and circuit. 
Good luck. 
mdr

mdelrossi1

thanks for the response. I asked a guy who does a lot of mods and builds his own gear and he said the same thing, that it's well built and designed so probably just tube roll. The Philips continue to sound awesome. I have some NOS Mullards coming in a couple days to try another flavor as well.