Frozzie, some good subs for the mild to moderately hot chiles that you should be able to find are the banana peppers, Hungarian yellow wax peppers and the Italian pepperoncini, red or yellow.
I've a friend who lives in Lille and became "addicted" to Mexican foods when she spent a year at UCLA back in the early '90s. I used to ship her "care packages" until she found that there were acceptable substitutes available near her home.
In one letter (prior to emails) she said that she had found a store that catered to Turkish cooks and which carried the hot peppers from Turkey that were nearly identical to the dried guajillo (pronounced wa-hee-oh), or Mirasol pepper when fresh.
The fresh peppers should be blistered over a flame and the skin removed. The dried peppers should be soaked till soft but you can also blister them lightly to make the skin easier to remove.
Wear gloves - if you can get the snug-fitting surgical-type gloves, they will save your hands (and eyes).
The seeds and ribs contain more of the capsaicin than the flesh of the peppers so you can mitigate the heat somewhat by removing them.
And if a dish is too hot, you can always add sour cream and burning in the mouth can be relieved with the same or with cream or whole milk. The casein in the cream will actually surround the molecules of capsaicin and carry it away. An emergency measure, if no dairy is available or permitted, is a teaspoon of sugar, held in the mouth till it dissolves.
Water does not help, nor does beer - in spite of what some people say. Enough beer and who would notice the burn?