Where can I find a high temperature non-conducting wire encasing?
You may like to explore the avenue of fibreglass. It is frequently used as high temperature wire insulation but you must verify the limitations before applying the actual. EDIT. Encasing Nichrome wire in mineral sheathing compound may be expensive unless you are able to buy it as you require but since you are talking about a TOASTER, such costs will be extravagant & unnecessary. I think that you will find that fibreglass insulation is used quite frequently in toasters. I haven’t seen MIMS in domestic toasters yet.
