Thank you for taking the photos.
The engraving is closer to a TC lock than an Investarms Hawken lock.
There are options that require some legwork on your part.
One option is to contact Track of the Wolf to see if they can match up your frizzen spring.
It could involve sending them the lock so the part can be fitted.
I'm not sure because I've never tried to match a spring.
Another option that was recently mentioned here is to contact Ed Cain by email for TC Parts.
He owned Cain's Outdoors and Mountain State Muzzle Loading which closed down in the past few years and he has a stock pile of TC parts.
His email is
[email protected] and send him the photos and ask him if he can help you out to fit the spring.
There's other reputable vendors that can do the same thing if they have the parts, such as Dixie Gun Works, Log Cabin Shop Lodie, Ohio and others.
If may be possible to fit a Lyman Investarms part, but to get one from Lyman the importer, you would need to order the parts list for the model that you want the part for that costs $1.
I suppose the part can be ordered over the phone but I don't know if all of their frizzen springs are the same for all of their different models.
Even the TC part if available may not be a direct fit.
It might be but who knows.
Someone just installed an Investarms tumbler in their TC lock and the part needed a lot of fitting to make it work.
So it depends how much fitting that you're able to do.
To have Track of the Wolf or Ed Cain size up or install the part can save a lot of back and forth and wasted shipping funds for the wrong part.
So I would contact 2 or 3 outfits by sending photos and see what they suggest to do.
And tell them that it looks like you have a clone of a TC lock.
You can contact Lyman and go the Investarms route too.
If anyone has a better idea they'll chime in after they read about it.
But until then I would send some emails and ask who to speak to about fitting the frizzen spring.
Maybe they can recommend the part over the phone or in an email.
These places have a lot of experience.
Track of the Wolf probably has 20 different frizzen springs, and they may already know the size you need if they see your photos.
Let us know how it works out and keep visiting this thread to see any other suggestions.