Generally, kids are disbudded sometime during the first week of life. However, if your little guy's are just now erupting, you should be okay. If they get to say, over 1/2 inch, they would be too big. I doubt that you will get 1/2 inch of growth in a week. Here are some good instructions...
Are you saying that the only disbudding iron you could find was $200.00? Jeffers has the X-30 on sale right now for $54.95, I believe. Here's the link www.jefferslivestock.com.
Okay, I just double checked the site. Apparently the sale ended and the X-30 is now $58.95.