Using non-rechargeable batteries on old HP calculators

[pocketRockets]

Hi,
I have HP-65, HP-67, HP-35 and Hp-25.
I also have a TI-58.

I have spare battery packs and power supplies for all of these, but since they're only collectors items they don't get used that much and I'm not good at pulling out the calculators to maintain a charge in the batteries.

Instead of continuing with the old rechargeables, I'd like to find a way to use alkalines when I pull out my calculators.

Were battery holders ever made for these calculators or does somebody make them today? I can find loads of rechargeable packs on eBay, but that's not what I'm looking for.