I could never find this link when people were looking for something like this.
I just came across it again, so I thought I’d better post it before I lost it yet again.
I made a similar probe out of an old airgun CO2 cartridge. The cable enters through the narrow end and the cartridge is then filled with thermal grease before sealing the end with silicone sealant. I get very accurate results with this DIY approach which cost next to nothing! :lol: