Trying to Identify 17 5 BP CAKDWELL

This looks like either an S380-18 or S385-18. The only difference between these two balances is the 'depth' of the bottom nylon shoe, or the heel-to-toe measurement, so compare both with your old hardware to see what matches best. In either case, choose 1750 as a new stamp option.

Thanks for the kind words! Truthfully, I was just very cold when we took pictures that morning. I am, however, still in school and enjoy writing, so I suppose you're not very far off! 

The shoe is the bottom nylon fitting that you're indeed showing in your photos. The depth is shown in the second picture, the 'heel-to-toe' measurement just below and perpendicular to where the metal channel ends. The illustration below better shows the difference between the 1" Series 385 shoe and the 1-3/32" Series 385 shoe. Double-check to confirm. If the shoe is any deeper than 1", then it's a Series 385. 

Our replacement balances come fully assembled, with new fittings and internal spring components. The video below shows how to install the new balances. 

Finally, yes--the stamp option indicates the weight range the balance is calibrated to support. For non-tilt window channel balances, technically the first two digits, in your case 17, refer to the height of visible glass in the window. This is usually one value fewer than the actual length of the metal channel (in your case, this should be 18"). The remaining digit(s) indicate the weight range the balance can support. So a stamp of 1750 (or, on your old balance, 17-5) can support a window sash in the weight range of 17 through 20 pounds. 

Let me know if you have any further questions! 

Comparison of the S380 and S385 balance shoes.