It's really fast to make your own envelopes if you get the We Are Memory Keepers envelope punchboard which is available from many sources and is very reasonably priced (less than $20). You can make many sizes of envelopes with this tool which is great IF you want to make different sizes lol. You could buy a lighter weight kraft paper to make your envelopes if your kraft cardstock is pretty substantial.
This endorsement is coming from someone with very little patience, so the tool must be easy-to-use haha.
1. When this punchboard was first introduced, some of the preprinted dimensions on the tool were incorrect but have since been corrected. To see what size envelopes you can make and, if you're so inclined, to be sure your tool has the correct dimensions printed on it, you can check the dimenstions on the WRMK website here:
2. Some folks are not happy with the A2 envelope size that this tool produces. I'm fine with it.
One place to buy (a little over $16.00) is Amazon:
Amazon.com - Envelope Punch Board // We R Memory Keepers
wrmk envelope punch board - Bing Images