manual pump w/ adjustable flanges

Mr

I currently use spectra s2 electric pump with size 19mm flanges. I’m not responding the best, or I should say it’s temperamental. Sometimes I’ll get a good amount out and the next pump I’ll get only an ounce. Hand expressing is a nightmare. It’s like peeing in the woods—goes everywhere. 🙄

Looking for manual pump w/ flanges that will accommodate my size.

Thanks.