[Phantasm]

What I've done is treat stormtrooper armor as Hardshell Armor from Pyramid #3/12 Tech and Toys, "More Ultra! More Tech!", which is analogous to a full suit of Light Clamshell (48 lbs, DR 30 at TL9). If you want it really pitiful, divide DR by 2 for making it TL8 plastic, or by 3 for TL7 plastic.

Multiply weight and DR by 1.5 for a suit based on the heavy clamshell, which would match Mando's initial durasteel armor.

I agree with giving beskar armor several levels of Hardened. I'd look into going 4 levels, actually, though Fett's armor in S2 was shown to have some holes in it from where the sarlacc's digestive system attacked him.

Lightsabers and blasters being as per GURPS Ultra-Tech seem viable. Using the Blaster and Laser Design article with some of The_Ryujin's additions for other blasters (such as the E-WEB we see in the final ep of S1) may give you more selection of weapons.

I not sure how the Tusken gaffi stick would work.