Sky Destroyer was only released in Japan. I don't believe there are any serious Famicom collectors on the site, so the selection of covers on TCP is minimal.
Newly appointed Cover Guru Akumu made a cover for Super Turrican here:
http://www.thecoverproject.net/forums/index.php?topic=368.msg21274#msg21274It no longer appears to be available, but perhaps he can reupload it if it's still in his possession. If he doesn't see this thread it may be worth sending him a PM and asking nicely.
Otherwise, Arseen has uploaded raw scans for the CGC project here:
http://www.thecoverproject.net/forums/index.php?topic=21248.msg193493#msg193493While I know you aren't looking for raws, perhaps someone will make you a cover using them as the source.
For your US SNES requests please see my post here:
http://www.thecoverproject.net/forums/index.php?topic=22865.0Any US game not on that list is not currently available, although some do have raw scans and are in the process of being created.
I am currently finishing up a cover for Izzy's Quest for the Olympic Rings, it will be available on the list above when it is done.
The image for Jelly Boy you linked is a PAL cover, if you are looking for the US release it is called Smart Ball.
The Legend of Zelda BS was never released in cartridge form and consisted of 4 different quests. There are a number of vertical covers available, such as a couple by monjici here:
http://www.thecoverproject.net/forums/index.php?topic=17496.msg154631#msg154631 but no horizontal covers that I am aware of.
nintandbox.net has a scan of Parodius here:
http://www.nintandbox.net/index.php/en/nintendo-boxes-project/SuperNES-SuperFamicom/Parodius/Perhaps someone will make you a PAL cover using this as the source.
Spiden made a US style cover for Parodius here:
https://app.box.com/v/CoversGalore/file/33219234173The color needs to be adjusted slightly to remove the off-black areas around the logos. I can do that if you'd like.
tiktektak made a PAL cover for Pop'n TwinBee here:
http://www.thecoverproject.net/view.php?game_id=8181If you want English on the back, Arseen has shared a scan here:
http://www.mediafire.com/view/36tn86x26aua83b/Pop%20n%20Twinbee%202%20Back.jpgMaybe someone could replace the German text for you.
maroxb just recently shared raw scans of Kid Dracula here:
http://www.thecoverproject.net/forums/index.php?topic=18952.msg204713#msg204713It's very possible someone is working on a cover. rockabilly1983 makes amazing Nintendo handheld cases, but I don't know if he takes requests. It may be worth sending him a PM and asking nicely.
http://andydecarli.com has raw scans of Toonsylvania here:
http://andydecarli.com/Video%20Games/Collection%20Pages/Collection%20Game%20Boy%20Color.htmlI'll work on a cover for you using these scans.
I'm sorry this list is full of so many raw scans when you specifically said you weren't interested, but it's good to get all of them in one place just in case one of our members wants to use them to make you a cover. Good luck!