There are all kinds of polyvinyl caps and such available at the local Menard's or Home Depot.....they usually come in sets of 4-8 in the bubble
pack or clamshell packaging. This gives you the option of having a couple extra in case you lose one or two. They're lots lighter than hardboard or plywood discs and WAY cheaper, & will not scuff the seasoning,,,,,,,,,,,,and 'specially so, if you pack the way you season........oven body downside-up with the lid topside-up on the legs of the oven. With the lighter lid on top of the legs of the oven body there will be less chance of abrading the most important part of the oven. Not to say that the seasoning on the underside of the lid when it is in the "cooking position and not the 'transport position....which are one in the same is not important

, but when was the last time any of you have had a prollem' with your dishes stickin' to the lid

....unless it was just a fancy trick in liftin that mass of sticky-buns out of the oven without the advantage of a hot pad?
Didy'a

yer' heads any in that description

. The individual boxes for each oven are the way to go for most of the seldom-used ovens, but for the two that you use the most....I'd say one box for the two of them and in the front of the compartment where they are contained. One huge yank and a grunt will get 'em on the ground and yer' good to go.