Solid State Preamp to replace tube unit

I'm either VERY LUCKY or an anomaly.  I have 3 tube amps and 2 tube preamps (McIntosh MC-225 paired with an Audio Research SP17, a Dennis Had Inspire "Fire Bottle" 45 paired with a Dennis Had LP3.1, and a Reisong A10 EL34 Integrated).  The stock Reisong tubes were replaced in 2018 with NOS tubes, the Dennis Had gear has Emission Labs 45 tubes I installed in 2018, the ARC tubes are more than 10 years old (I bought it in 2020 from the original owner and he had receipts where he replaced the tubes in 2012) and the McIntosh has Westinghouse 7591 "Made For McIntosh" tubes that appear to be original based on my research (I bought it from the original owner in 2021 who bought it in 1963, my year of birth -- he said he had never replaced the tubes and the technician I had go over it said all tubes looked original, it had been in storage for 20 years).

Each system gets played several times a week, for an hour or two each session.  For those of you with far more knowledge than I have...what am I doing right??  I'm not complaining, far from it.  But how can the OP go through tubes as he said and I have Dorian Gray tubes??

@tomic601 

1961 -- Amazing. You have been the first person that responded to my post, so I did some online research today on my own. I discovered NUMEROUS comments in Forums and articles that said exactly what you said -- the MC225 and MC240 were legendary for being "easy" on their tubes. Especially those original Westinghouse tubes with the "Made For McIntosh" green print. Many people said they were still using the original tubes...60 years or longer. That is just astounding to me.

I dread the day my luck runs out on the McIntosh tubes. Last time I checked, there were still some NOS available at times, but it always worries me when the website says "Call For Pricing". I have thought about just buying a backup set while I can -- I can’t take the money with me! While I’m in a spending mode, I’ve also been looking for an MC240. I have always been told by my older McIntosh owner friends that the MC225 and MC240 are and were the best sounding amps McIntosh ever built. I compared my MC225 to a friend’s MC275 and preferred mine. Maybe it was confirmation bias, maybe not, but I’d like to hear an MC240 in my system.

@tomic601 -- I have bought from Brent Jesse when I was getting tubes for my new Reisong A10 (absolutely amazing little amp -- I saw a review by Steve Guttenberg and thought "What the hell".  It cost me a total of $345 and that included shipping!  Paid another $120 for upgraded tubes.  Awesome amp for my bedroom streaming system).  I looked at your pictures...beautiful.

@elliottbnewcombjr -- I agree with your comment!  I try to keep a back up set of tubes for all my amps and preamps -- the MC225 is the only one I haven't purchased them yet.  Your suggestion makes great sense...start using the new set and keep the originals as back ups/nostalgia.

@dogearedaudio -- I bet those monoblocks were sweet.  I've seen a couple for sale and they aren't cheap!  And the tubes aren't either!