I picked up a couple SAS HDDs that I would like to place in an external enclosure. However, I am struggling to find any that supports SAS HDDs. Does this exist? Could you please recommend any? I would ideally like that enclosure to support JBOD or RAID 0/1 and have a USB interface. Anything below $200 would be alright. No other constraints (power / size / noise). A simple search did not yield any results.
you can just amazon "external sas".
for example "HighPoint RocketStor 6414S 6Gb/s SAS/SATA 4-Bay Storage Tower Enclosure" for $289.
you are not likely to find anything economical, not with SAS. SAS is server work environment, not for home use. If you picked up a couple sas disks you may want to just cut your losses now if this is for personal use. You will still need to get something like an SFF-8086 external sas cable to connect the sas enclosure to your computer, and then you will need an internal pcie SAS [raid] card within your pc- brand new a genuine dell of lsi/avago can run you $1000 depending where you buy it from otherwise you can get lucky finding one for $100 on amazon. A used Dell PERC H730P for $245 i see on amazon. But you will need to cobble it all together, and you take your chances.
you would be better off amazon'ing a SATA external where 4+ TB is the norm now and very economical. Even if you got those sas disk(s) for free, it's not worth it when sata disk prices are as low as they are.
note: SAS hardware can support sata disks... sata disks can plug into a sas backplane and they make SAS-to-SATA breakout cables. But a SAS disk cannot plug into a SATA connector. And be aware there are various SFF-#### cables supporting sas so you have to make sure all your hardware can plug into each other.