Maybe you can buy directly from their company, not through eBay. Especially with eBay/Amazon/etc. you got to keep an eye on the
total cost though, you may end up paying much more for shipping than the merchandise if they don't combine orders. Maybe they do?
Hops, vacuum (re)sealed or with as much air squeezed out as possible, and stored in the freezer, will easily last for a couple years.
I don't think buying hops by the oz is all that much burden. Depending on variety and origin, hops here in the U.S. run between $1.50 (e.g., Cascade, U.S. Fuggles) and $4.50+ (e.g., Nelson Sauvin) if bought by the oz. I bought whole pounds of common hops for as low as $5, from harvests 1 or 2 years before. Vacuum packed and freezer stored they're just as fine as this year's. Moreover, if the seller doesn't declare the harvest year chances are they may well be from the year before, or even older.
Even a heaped tablespoon of
hop pellets swells enormously when wet, make sure the "teabags" are large/roomy enough, so wort/beer can flow through unrestricted for maximum extraction.