Vinyl window replacement part

Good afternoon. There was a pop sound on the window when it was opened. Now it will open but will not stay up. My husband took these parts off but we have not been able to find replacements for them. The window is double hung and tilts out. Thank you. I think I need a 180 coil balance from looking at your parts but don't know what else I need. Look forward to hearing from you. Vicki