Okay, when heyco called me back today to verify my question of whtrher or not a 1" diameter heater would fit in the .59"- 1" Cord grip (it does), the women told me how to get a free "Sample" product.
It'very easy. On the home page right underneither "Distributor/ Rep and Part umber Search" on the right hand side of the screen at the top, you will see a tab called "Catalog Sample Request". Just click on the tab and it take you to the order form. Fillin your Nae, address and shipping info as well as the part number (#8437 for the .59" - 1.0") or (#M4522 for .787" - 1.02").
Here is the list Just look for those number and you can order something larger if need be! You can also order it in black or grey. Your choice!
Here is the Free Sample ordering Form Page
Fro some reason the sites link isn't working but give it a minute. It should be back up and running fine!