Help Identifying Parts for Sliding Window

Good afternoon, 
I hope you’re doing well.I’m reaching out to request your help identifying a replacement part for a sliding window.
Attached you’ll find a photo of the existing plastic piece we have as a reference. We need to order this part, as well as the corresponding rollers/wheels that work with it, in order to repair a sliding window.
Could you please help us identify the correct part number and the compatible rollers so we can place an order?
Thank you in advance for your assistance, and please let me know if you need any additional photos or measurements.