I have written a python script to do this, but you need to realise there are infinity keys that can be derived from a seed...
https://bitcointalksearch.org/topic/m.17027986
It's a starting point, the completed script was only sent to the OP of that thread in PM, and since he payed a bounty, i'm not sure if i can publish the complete works... That being said, this post should be more than enough to put you in the right direction, even without much scripting experience.
But TBH, if you're really that paranoid about any wallet, the only completely trustless scenario for somebody that is not able to verify and compile the sourcecode himself, is to use an offline wallet setup (install electrum on a pc that never goes online, export the xpub, save it on an usb stick, transfer it to an online pc, import the xpub, generate transactions on the online pc, transfer them on an usb stick to the offline pc for signing, and back to the online machine for broadcasting).
I'd personally also suggest to use a decent, tested, program to generate your seed words (i recommend electrum, altough you seem to have trust issues ), not only because a random seed is not allowed, but also because humans are a bad source of entropy.
This is not an easy setup, IIRC you need to start the offline electrum using a couple extra parameters, but it should be as close to completely paranoid as possible... Maybe with the exception of a paper wallet.