Heh, actually, I used to make a lot of icons back in the day. I still have hundreds of .ico files stored on on one of my hard drives
More to the point though, you can always try
http://www.iconarchive.com or
https://www.deviantart.com/customization/icons/
Unfortunately icons for rather obscure indie games like the ones you mentioned can be hard to come by.
I guess you're just looking for some hi-res (256x256) icons to replace the small default ones? If you can't find it, you can easily create one yourself. IcoFX is a great tool for making icons from any image. I used it to convert the .png files I created to .ico format, but it has some not-so-basic editing features It's a commercial software now, but it used to be free. Look for a download of version 1.6.4 (the last freeware version of IcoFX) or hit me up and I'll send you a copy.
Creating simple icons by yourself often really is a matter of minutes
