Tithing envelopes

I don't know how this came to be, but in our inventory in my clerk's office, I've counted about 100 gray tithing envelopes and about 2,000 (yes, two thousand) donation slips to go with the envelopes. I know I could order just the blank gray envelopes on store.lds.org, with no bishop's address printed on them, but those are 5 cents each, meaning that 900 of them would cost $45. The funny thing is, on store.lds.org, they sell one set of 900 gray tithing envelopes, all with the bishop's address printed on them, and with 900 donation slips to go with them, all for only $33.75!

Now, my ward doesn't go through too many tithing envelopes quickly because it's a small ward and a lot of people pay tithing online, but I'm puzzled as to what do about the big surplus of 2,000 donation slips. It would be quite wasteful to just throw them away.

So I've thought of a few solutions below (one or two of which may sound a bit odd), but if anyone could provide me any other advice, please help!

1). Ask store.lds.org if I can just order the 900 gray envelopes without the donation slips to go along with them.

2). Most of the packs of 225 donation slips that we have are still unopened in plastic wrap. Could anyone, or even store.lds.org, take those?

3) Make my own tithing envelopes. The #6 3/4 size white envelopes from Staples (which the Church has contracted with to provide office supplies) cost $8.26 for 500 envelopes. I could order light gray paper dye to make the envelopes gray. (I realize that gray envelopes stand out better than white envelopes and so are less likely to get lost, which is especially important when money is inside of them).

It could have been that when a bishop was released and a new one was called, the envelopes with the old bishop's name and address were disposed of. That would leave you with a shortage of envelopes and a surplus of donation slips.

If any are the older style without a place for the MRN..... Throw them away and don't even think twice about it.
If I remember right several years ago the wards were all sent a box of the new style receipts to replace the old.
I've been a clerk in 2 wards and both had a surplus of several packs of the receipts.
I once ordered a new box of 10% envelopes and the Bishop was released 3 weeks later........
IMO I would not make my own envelopes unless just a few in an emergency like if you run out before the new order arrives.
The gray envelopes are easy to distinguish from other correspondence so I know not to touch them when they contain donations ............