The now well known Samyang prime lenses (8mm fisheye f/3.5, 14mm f/2.8, 85mm f/1.4) comes in various mounts, but not the SA mount. I did contact them last year, asking if there was a plan to to release the samyangs lenses in SA mount, the answer was "No". Then I asked if it could be possible to order a 85mm with the EOS bayonet replaced by a K ring (but without the aperture lever). I'm still waiting for an answer.
But, last month, at the Paris "Salon de la Photo", I get a chance to manipulate those Samyang lenses, and try them on my SD14 (just holding them in front of the camera). I particularly observed the way the rear element move or not.
Convinced a canon EOS Samyang would be easily converted to SA mount (just had a doubt about how the EOS ring was in any way linked to the aperture mechanism), I did buy a 85mm.
Three days later, after unmounting the EOS ring and a little DIY to create the SA ring of the right thickness out of a M42/K adapter (total cost of the conversion is around 5-7€), I now have a great short tele lens with a wide aperture. Results are really good, and I doubt you can get similar quality for the price (275€ for the lense + 5€ for the conversion).
The bonus is, the conversion is totally reversible, so even if you have a problem with the lens while under warranty, just remount the EOS ring and bring the lens to your dealer.
Here is an example shot:

Samyang 85 on SD14
Sure Sigma users should ask samyang for a SA mount version of their lenses, as it would not demand a huge work for this.
Maybe it could be possible to simply provide a SA mount ring on demand, this way, any Sigma user could buy a Samyang in EOS mount and make the conversion itself?
Regards
But, last month, at the Paris "Salon de la Photo", I get a chance to manipulate those Samyang lenses, and try them on my SD14 (just holding them in front of the camera). I particularly observed the way the rear element move or not.
Convinced a canon EOS Samyang would be easily converted to SA mount (just had a doubt about how the EOS ring was in any way linked to the aperture mechanism), I did buy a 85mm.
Three days later, after unmounting the EOS ring and a little DIY to create the SA ring of the right thickness out of a M42/K adapter (total cost of the conversion is around 5-7€), I now have a great short tele lens with a wide aperture. Results are really good, and I doubt you can get similar quality for the price (275€ for the lense + 5€ for the conversion).
The bonus is, the conversion is totally reversible, so even if you have a problem with the lens while under warranty, just remount the EOS ring and bring the lens to your dealer.
Here is an example shot:

Samyang 85 on SD14
Sure Sigma users should ask samyang for a SA mount version of their lenses, as it would not demand a huge work for this.
Maybe it could be possible to simply provide a SA mount ring on demand, this way, any Sigma user could buy a Samyang in EOS mount and make the conversion itself?
Regards