May not be what you are after but I would look at nuPickers, I used their DotNet PrefectchListPicker datatype to select options added via an archetype repeater on the root of my site. With this data type the options made available can be derived via a class.

My code:

public class RegionOptions : IDotNetDataSource
{
    IEnumerable<KeyValuePair<string, string>> IDotNetDataSource.GetEditorDataItems(int contextId)
    {
        if (contextId > 0)
        {
            var umbracoHelper = new UmbracoHelper(UmbracoContext.Current);
            var currentNode = new Node(contextId);
            var homeNode = umbracoHelper.TypedContent(currentNode.GetAncestorByPathLevel(1).Id);

            return RetrieveRegionsFromNow(homeNode);
        }
        else
        {
            var umbracoHelper = new UmbracoHelper(UmbracoContext.Current);

            var homeNodeTest = umbracoHelper.TypedContentAtRoot().FirstOrDefault();
            return RetrieveRegionsFromNow(homeNodeTest);
        }
    }

    private IEnumerable<KeyValuePair<string, string>> RetrieveRegionsFromNow(IPublishedContent node)
    {
        if (node.HasValue("regions"))
        {
            var regions =
                node.GetPropertyValue<ArchetypeModel>("regions")
                    .Fieldsets.Select(
                        fieldset => new KeyValuePair<string, string>(
                            Regex.Replace(fieldset.GetValue("region"), "(?: |,)", ""),
                            fieldset.GetValue("region")));
            return regions;
        }
        return Enumerable.Empty<KeyValuePair<string, string>>();
    }
}

Instead of getting the property from the home node you would obviously target the parent of 'currentNode'.

Other than that you will have to create something bespoke yourself.