Batteries are not really an issue. Anybody using hearing aids (except me!) will have no trouble finding the much-vaunted "button cell batteries" for any spotmeter that needs them.
1 spot meters are very, very, very accurate when you know what you are doing with them e.g. at a base leel, highlights, shadow, mid-tones, average of all of them and additional compensation for filtration etc (critical for polarisers). Your metering technique will get a solid workout (you might even lose a few hairs...) using transparency film which is less forgiving of mistakes than neg film, but is really an excellent way of mastering spot metering.