If you rarely need it then you could print you own ID card and wear it, it's quite cheap to do. If you are asked, no you don't have an ASIC but you have a ID card with you photo on it plus other ID available. Then if asked why no ASIC refer to the rules which state only required for frequent access and that you rarely visit (info is on this forum). If you believe they are likely to demand it call ahead and tell them no ASIC so they are required to escort you.
Wow that brings back memories! Not any more of course, a more docile and supine group of sheep you would scarcely find.