i have a 1978 kelty serac an i am looking for replacement shoulder straps

Tech Specs:

Material:

600D Poly ripstop, 600D poly oxford 

Volume:

[Khaki] 3900cu in (64L); [Woods Green] 3950cu in (65L) 

Suspension:

External 

Hydration Compatible:

Yes, bladder sold separately 

Torso Adjustment:

Yes 

Detachable Pack:

No 

Sleeping Bag Compartment:

Yes 

Rain Cover:

No 

Access Types:

Top 

Pockets:

1 Main compartment, 1 sleeping bag, 1 top, 5 external zip, 2 mesh bottle 

Snowboard Carry:

No 

Ski Carry:

No 

Gear Loops:

3 Daisy chain 

Ice Axe Loops:

1 

Shovel Pocket:

No 

Weight:

[Khaki] 5lb 6oz (2438g); [Woods Green] 5lb 7oz (2466g) 

Recommended Use:

Backpacking 

Manufacturer Warranty:

Lifetime