What radioactive sources do you use and what do you store them in?

If you want to get hold of a strong Radium source in the UK a good place to look is on ebay - search 'Old WW2 aircraft instruments'. You need to be a little careful but I picked up a heavily radium-painted instrument for just £14, Look for a dark yellow/brown painted dial. Prices vary, some types being more popular to a collector than others - nothing to do with their radioactivity though so don't buy premium collectables.

*Treat these items with care, do not try to open the instrument to extract the radium-painted parts. The paint degrades over the years and there will almost certainly be loose paint dust inside which is a contamination hazard. The collectors of these things likely pay scant regard to their radioactive properties but you and I know better. Store it in a sealed plastic bag itself placed inside a labelled glass/plastic food container.

This is the aircraft instrument (?) I bought from Ebay for £14. It's a bit hot with ~1500cps (RC103) despite it being in a thick sealed case and also inside a plastic bag.

 

You can get smoke detector ionisation moduesl from Aliexpress. Just look for ionisation smoke detector, they contain about 30Kb of Americium

I have a Thoriated Gas Mantle (Th-232) that I have used as well as some older ceramic plates I purchased at a thrift store. Both were reasonably active.

Almost forgot. A couple years ago I coworker offered me a calibrated source. This was an old calibration reference that was no longer used. Details are sketchy at the moment. Anyway he said he would send it to me but it never arrived. He left the company shortly after but I never learned the fate of the source. Evidently was in heavy shielded box so it must have been fairly hot.