Does anyone have experience with purchasing a non-Astra naked/bottomless portafilter for use with an Astra? I'd like to buy a bottomless PF but don't really want to spend $150 buying it directly from Astra. My understanding is that the Astra is very similar to an E61 (58mm). TIA!

ECM angled portafilters worked for me perfectly. About $70 or so