Rubber oring sealing can be produce by EPDM,FKM(VITON),SILICONE,SBR,NBR etc rubebr material,the price of each color for silicone rubber material is the same.But the price of black for another rubber material is the cheapest one,if you need white/yellowing/red etc color,that will be ok,but the price will be a little higher.So are you interested in it?if yes,then pls contact us freely as following details:
Shiny
Yiho Polytek Co.,Ltd 
Factory Address:      No.199, Dongyang Road,Tongan District,Xiamen,Fujian,China
Operating Address:  Room709,No.388 Qishan Road,Huli District,Xiamen,Fujian,China
Tel: 86-592-6038809 Fax:86-592-6036089 M:+86-15960227471
http://yiho-seal.en.made-in-china.com                                                
 
https://yiho-seal.en.made-in-china.com 

Additonal parameter of silicone oring:
It is an elastomer (rubber-like material) composed of silicone-itself a polymer-containing silicon together with carbon, hydrogen, and oxygen. Silicone rubbers are widely used in industry, and there are multiple formulations. Silicone rubbers are often one- or two-part polymers, and may contain fillers to improve properties or reduce cost. Silicone rubber is generally non-reactive, stable, and resistant to extreme environments and temperatures from -55 °C to +300 °C while still maintaining its useful properties. Due to these properties and its ease of manufacturing and shaping, silicone rubber can be found in a wide variety of products, including: automotive applications; cooking, baking, and food storage products.