Balancer 27.6 lb., 34 "

See our S395-34. For a stamp, if the window sash weighs exactly 27.6 pounds, go with a stamp option of 3340; this will support a sash in the weight range of 23 through 28 pounds. 

The difference in style of the top fitting is perfectly fine in this case. That component in particular serves a very simple function so it doesn't have to be 100% exact. 

As for this plastic part, this is called the top sash guide. Yours is a match for our 18-171.

If your sash is 27.6 pounds then the 3230 stamp will not be strong enough to support it, since they only carry 18 pounds max. You want the 3340 stamp that Bob recommended back on the 15th. 

Once you're ready to place an order, you may do so directly on our site at your convenience. 

Yes, the 3340 is calibrated assuming that two balances are holding the weight of the sash. You don't want to add their individual calibrations together.