Do I qualify for VA survivor's pension if my dad served in the Vietnam war?

The VA Survivor's Pension (otherwise called the Death Pension) is a tax-exempt advantage paid to qualified wards of perished wartime veterans.

VA Survivor's Pension Eligibility
he expired veteran was released from administration under other than despicable conditions, AND
they served two years or a greater amount of well-trained with in any event 1 day during wartime. Furthermore,
you are the un-remarried enduring life partner or unmarried offspring of the perished veteran, AND
your countable pay is under a yearly breaking point set by law:
The Death Pension Payment Amount
VA pays you the contrast between your countable pay and the yearly pay limit which portrays your circumstance (see outline beneath). This distinction is by and large paid in 12 equivalent regularly scheduled installments adjusted down to the closest dollar.
Current Income Limits
On the off chance that you are a... Your yearly pay should be not exactly...
Enduring companion with no ward children $9,344*
Enduring companion with one ward child $12,229**
(Add $2,382 as far as possible for EACH extra youngster)
Housebound enduring life partner with no dependents $11,420
Housebound enduring life partner with one dependent $14,300
Enduring mate who needs help and participation with no dependents $14,934
Enduring life partner who needs help and participation with one dependent $17,815
Enduring kid (no qualified parent) $2,382
Note: Some pay isn't tallied toward as far as possible (for instance, government assistance advantages, or a few wages procured by subordinate kids) * To be deducted, clinical costs should surpass 5% of the Maximum Annual Pension Amount ** To be deducted, clinical costs should surpass 5% of the Maximum Annual Pension Amount
The Death Pension Application Process
You can apply by rounding out VA Form 21-534, Application for Dependency and Indemnity Compensation Or Death Pension by Surviving Spouse or Child. In the event that accessible, join duplicates of reliance records (marriage and kids' introduction to the world endorsements).

No you do not.  

in general, you can't get such a VA benefit and disability [SSDI] at the same time.