Does anyone know what these plans are and if they are rollable into an IRA?

c18 plans were established as retirement plans by unions for their members when employers refused to make contributions to a qualfied plan. Employees made contributions to the trust which were deductilbe as union dues under early IRS rulings. Earnings are deferred. Under current law contributions are elective contributions which can be deferred up to $7,000. See IRC 219(b)(3). Under c18 contributions are considered to be elective deferrals under IRC 402(g) subject to rules for 401k plans. Check the 1099 instructions for rollovers. There are fewer than 20 active plans left.

Doesn't appear to be rollable. Under IRC 402©, an eligible retirement plan is a 403(b) or a 401(a) qualified plan. 501©(18) is neither of those, though it contains elements of them.