Hi, my female Blossom had cherry eye in both eyes, and I used Refresh tears from the drugstore, before I had them surgically repaired. You can use pretty much any eye drop that we can use from the drugstore. You can ask the pharmacist which is a good brand as well. I think refresh tears are about $15.
HRH has dry eye and is on optimmune gel from the vet. It costs about $30.00 a tube, however one tube lasts about 6 weeks to two months so it only costs about $15.00 to $18.00 a month. (our vet does not charge an office visit when we go in for refills even if he checks her eyes out quickly)
Even a decent over the counter drop is $8.00 a bottle and doesn't last as long, so really the optimmune isn't that horrid. And it has helped ever so much more than the over the counter stuff did before we got her on this regimen.