Rob, best of luck getting it to a new home. The 375 H&H is such a versatile round. You can use it on almost anything without going into overkill mode (says the American!). Do you hand load? I've used heads as light as 180gr which is great for small critters and plinking.
I know what a PITA it is in the UK to get expanding heads for the 375. In order to get mine, I booked a red deer hunt in Scotland. I got the gun originally for an Africa safari and they would not let me buy any ammo for it first! (said I could buy in Africa when I got there) They were unmoved when I explained you can't go to Africa where the animals have a Ph.D in People Pounding without being completely familiar with your rifle. Hence, the stalking in Scotland. The 375 is analogous to the 10mm which "ze Germans" use on Red Deer and therefore must be allowed in the UK. See, the EU regs are not all bad ;-0
I had to wait until I got back to the states to use it on everything else. Even though the 375 is great for everything (well, maybe not groundhogs or rabbits), getting land approved for it is almost impossible. Bisley almost had a heart attack when I wanted to shoot it out to 300 yards.
I sold my Mauser M03 375 before I repatriated as I already had a Weatherby stainless 375 back home. I used the proceeds to upgrade to the M03 Africa in 416 Rem Mag.
Anyway, it would be a real shame to let it go as it is good for so much more than Africa. But if it really must find I new home, I hope it finds the right one.
Cheers from over here,
Cole