The last Mac that had a buit-in SCSI port was the Beige G3, discontinued in early 1999. However a lot were built and they still show up in working condition on the used market for pocket change. If you decide to spend $10 on one, go for the mini-tower--not the All-in-One or the "desktop" (flat case) model. The tower is much easier to service it it needs some rehab. I have two of these but Chicago is long way from teh wilds of Idaho!
If you buy a Beige G3: the internal backup battery, or PRAM" battery, is likely DOA. The Biege G3 can get very cantankerous if the PRAM battery is dead or weak. My advice--buy the new PRAM battery when you buy/borrow the computer. 1/2AA 3.6V lithium--$5 or less online; probably over $20 at Radio Shack where their part number is 23-026
There were PCI adaptor cards that gave SCSI support to later Mac models that lacked the built-in SCSI port. However, they are now hard to find.