Head bolts on a K341 in 169
 

My K341 on my 169 has hex head bolts instead of studs for the heat shield/muffler support. I plan to replace these two bolts with studs, and while I am at it, I will replace the remaining head bolts and washers, as I'm unsure if the existing ones are the correct size and hardness.
Does anyone have a good source for any of these bolts/studs? I am planning on using these if no suggestions:
https://www.amazon.com/gp/product/B0...HERA9T9K&psc=1

https://www.amazon.com/gp/product/B0...0UH9VAFQ1&th=1

https://www.amazon.com/gp/product/B0...KIKX0DER&psc=1

Here is a picture of the studs I mostly need the information for... not my engine; I borrowed the picture to show what I need.

You might also look here....
https://www.ebay.com/str/theboltbarn

Any hardware store worth its salt will have all these and more in stock.
You only need a few.

That is part of the problem, primarily only Lowe's and Home Depot here. The drawers are unsorted, empty, or 4x the normal cost.
By the time I make it to a real hardware store and celebrate success or leave empty-handed, I can order online and have it delivered and be wrenching instead of looking. Just have to make sure I am ordering the right parts.

Thanks! I will check them out.

Whatever
Ace Hardware, it's a hardware store