La Tene shield materials?

[Dan D'Silva]

Hello.  I'm back at college and once again up to some personal woodwork on the sly.  So I'm considering doing a small La Tene-style shield, about two feet tall, with proper one-layer plank construction this time.

The boards I can get at nearby hardware stores include American poplar, red oak and soft maple.  I know poplar is supposed to make a good shield and I've used it on several (unfinished) ones, but would you consider any of these acceptable from a standpoint of both historical accuracy and functionality?

If I go with oak, do I need to worry about any iron/steel fittings rusting?

Is there any facing that could be described as typical -- woven fabric, felt, tanned leather, rawhide?  Or should I just pick a historically-plausible material as suits me best?  If the shield's just one layer of planks, then I'd want it to have some kind of facing (and backing).

How is the wood boss/spine attached?  Is it also faced?

Thanks for any advice.  If I go through with it, it might take a long time to complete among all my other projects -- I'd just want to get the major shaping of components done this semester.