There's a number of early (non Celis) E39 Touring Amber top rear lenses on ebay right now!
One pair (they're listed individually) would come to £28 delivered to me if no one bids. There's a few sets/items at £15, plus £5 delivery, so around £40 for a pair delivered. The last two sets of these lenses I sent across came to around $50-60 USD to send, so perhaps for around $100-150 USD these would be landed at your door.
Good thing is they're always listed, due to as mentioned above, no one really wants them, so anytime any of you are ready to want a pair, it'll be relatively easy for me to sort out - so just drop me a PM !