In general we do not keep stock of parts. If a part is being highlighted as having insufficient stock it is because there is currently not enough availability in the supply chain for the number of units you are trying to order.
If this applies to one of the parts you are using you can either 1) choose an alternative part that can be used as a substiture or 2) let us know the lead time of the part.
On Digikey, if the current quantity is 0 you can click on "Check Lead Time" (listed under Product Overview) and enter the number of units you need.
On Mouser the information can be found by clicking on "View Delivery Dates" under the On Order section.
We have found the lead times listed on Digikey and Mouser to generally be very accurate.
For hard to source parts you may need to contact the part manufacturer directly.
Once you know the lead time on a part you can add it to the part using the "Supply Pricing" popup window. After adding this information the estimated ship date will automatically be adjusted in the quote.
At the moment our system only lists the availability from a single distributor. If a part is being highlighted as having insufficient stock, but you see that there is enough stock available from multiple distributors to satisfy the total number of parts needed then please contact us and we can fix that for you.