What did you create this with? If you cannot do an alpha channel, can you put a solid colour in the background? That will allow me to easily remove it. Some notes below on green screen colours...
Chroma Green can be broken down in many different ways. Here is green screen green as other values useful for both physical and digital production:
Green Screen as RGB Color Value: 0, 177, 64
Green Screen as CMYK Color Value: 81, 0, 92, 0
Green Screen as Hex Color Value: #00b140
Green Screen as Websafe Color Value: #009933