We like the Bard Monopty disposable core biopsy instrument. BardBiopsy.com
We recommend using the monopty 14g x 2.2 cm (cut) and 16g x 2.2 cm (cut) for dogs >30 pounds and 18g x 2.2 cm (cut) for dogs <30pounds. For cats we use the 18g x 1.2 cm (cut).
You can reuse them up to about 10 cuts or so before they start to dull. They can be cold sterilized then close the package with tape and gas sterilize and keep sealed until ready to use.