If you were located in the UK I'd recommend ordering from us here: www.3dexfilament.co.uk as I'm sure we have what you're looking for. Get in touch via support@3dexfilament.com if you're interested though.

With regard to the hobbled bolt slipping have you tried increasing the tension of the wheel that keeps the filament against the bolt? The wheel on my printer is incredibly tight and Ive never had issues with filament slipping. However, if you've tried this then maybe its small variations in filament diameter or finish. It must ruin any print that it occurs on?