Benzocaine is only slightly soluble in water:
Soluble in water (0.4 mg/ml at 20° C), methanol, chloroform (500 mg/ml), ethanol (50 mg/ml), and ether (250 mg/ml)
https://www.scbt.com/scbt/product/benzocaine-94-09-7
Click on ‘Technical Info’ tab
Most chemical substances become less soluble as temperature decreases.
You may wish to add another, or switch solvents
This 1945 patent lists its solubility in several solvents
https://patents.google.com/patent/US2457188
You may wish to stick to a proven pharma recipe.
It looks like many of them use polyethylene glycol
…In addition, the vehicle composition might have an effect. Polyethylene glycol is used as the solvent in benzocaine solutions because the local anesthetic is poorly soluble in water.61,62 In our study, the concentrations of polyethylene glycol in the 20 percent benzocaine, 10 percent benzocaine and vehicle gels were 77 percent, 87 percent and 97 percent, respectively…
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3844156/
Just curious on what you plan to use the benzocaine for?