The SCSI CD-ROMs would probably work, although I don't think you'll have much use for them in OS 1.3. Although there has to be some kind of CD-ROM drivers for 1.3 available somewhere considering the CDTV and the A570, you'd be better off with OS 3.1. Not just because of CD-ROM support but it will improve the overall functionality of your Amiga.
OS 3.1 can be bought as ROM-chips and disks from
www.amigakit.com or, if you're lucky, on eBay or similar sites. Failing that, you can buy Amiga Forever (
www.amigaforever.com) and use a program to load the kickstart 3.1 image to RAM, faking a 3.1 ROM.
