Are you looking for concours correct parts for your restoration?
IF so there are a number of commerical places and shops that can provide you with finished A arms - ready to use assembles or they will refinish ones that you find.
Tie rods can be refinished originals (understanding that they are not recommended for driving) reproductions from Rare Parts (see threads and articles on this site) are your two options.
For coil springs you can purchase replacement ones but those will typically be replacements rather than originals and might sit a little odd afterwards. Other items are likely ones that will have to come from a donor car so seek out someone rebuilding their 70 and offer to by their old stuff or find someone that travel the swap meets and wrecking yards. For those placing ads on sites like this would likely help you find what you need. Make sure you list all the related cars that used the exact same pieces that your looking for to improve your chances
Good luck
