There nothing special there just throw away foam ear plug. Most likely ear brand plugs could be anyone. There very popular with industry an supply house should carry them. They appear to moldex brand plugs.
Shoot an email to Howard Leight. Years ago I mailed them a letter (remember letters) and they sent me a giant box of samples of multiple styles that lasted me for quite a while.
i bought a little dispenser of the moldex ones for the shop, just helps me to remember to use them when needed. work great and are pretty comfortable compared to some others i have used, plus having alot of them available keeps me from reusing them and jamming dirt or soot in my ears http://www.mscdirect.com/product/00326280
I've used the above for years as they do not have to rolled and inserted. Pushing the center pin thins out the plug and it slips right in. Being corded they hang around the neck till needed.