Hi, I'm having problems finding CREB and pCREB antibodies that tag the same proteins in my blots. (see attached)

We are testing between 5 and 15ug protein loads from mouse hippocampal cell lysates, run on 15% gels at various dilutions from 1:500 to 1:8000. When we did this with the CST phosphoCREB (Mouse, mono, #9196), and the CST CREB (rabbit, mono, #9197), the pCREB appeared at the right molecular weight (~43kd) with a nice crisp single band, however the CREB bands were between 35 and 25kd. We tried again with an abcam CREB (ab32515, rabbit, mono), and while it gives us a nice crisp band, even at 1:4000, it ladders out at a higher molecular weight than the phospho - (around 50kd) - see photos attached. I'm so frustrated - anyone have a recommendation for a good CREB antibody produced in RABBIT for WB? (We have already probed for pCREB using the CST #9196 (mouse), and I'd like to be able to reprobe the same membranes with a RABBIT antibody to avoid having to strip.