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Thanks for posting. It looks like you have either Series 380 or Series 385 Channel Balances. The only difference between these two balances is the 'depth' of the bottom nylon shoe, so compare with your own balance to determine the best match. You will need to measure the length of the metal channel, not including the nylon attachments at either end, to determine the right length. Finally, you'll need to select a stamp option. If there is no stamp code on your balances, weigh your window sash. You can then match that exact weight with one of the correct stamp option. 

As far as your top sash guide goes, this exact model is no longer made, but we've found that our 18-171 is a possible substitute. The only issue is that the 18-171 has a taller head than your old guide, so you'd need to cut it down to fit it beneath the sash rail.