Are these also compatible with a PRimera LX 600? Are they perforated as one of the reviewers mentions?

The RL2798 is perforated between labels. The label and core size meets the specifications for Primera's LX600 printer model as well.

can you get these labels perfed?

The RL2798XW does have perforations between labels. If you're looking for a custom configuration with additional perforations, we'd be happy to create it for you. You can reach out to Customer Support at 888-575-2235 or send a request by submitting a support ticket at the link below. https://www.onlinelabels.com/Support/SupportRequest.aspx

Can this label be made in a 3.5 X 5? If so how much does that cost and what lead time is there?

We'd be happy to create a custom size for you. You can submit a request at the link below or reach out to our Customer Support Team at 888-575-2235. https://www.onlinelabels.com/special-order-custom-size-labels.aspx#rolls