Hi Mikey!
Relatively cheap, long-lasting, yet still good quality? How 'bout a standard Deore? I chose that option on my Sherpa precisely because it offered such great value for the money, and had steel inner- and middle-rings, which should be long-lived -- especially in the sandy, gritty desert environments where I often travel. It has a nice appearance that belies its (relatively) bargain price. Spare 'rings are readily available for a good price too, so if the combinations that are available fit your needs it might be worth a look. Keep in mind, it requires an external bottom bracket as well.
Best,
Dan.